Articulated beds have only recently achieved significant commercial success in the residential market and previously such beds had been marketed for the most part as a hospital or nursing home product, and with such objectives have been over-designed and overly complicated and thus too costly for the residential or home market.
Over the last several decades, articulated chairs and sofas have achieved some commercial success in the residential market but only recently has such technology been adapted for the residential articulated bed marketplace.
A primary consideration in the design of articulated beds and components, therefore, in the residential market is ease of shipment because a container the size of an entire assembled articulated bed would not only be excessively large but too heavy for a single delivery person to bring into the home to install.
One attempt at solving this problem is illustrated in the Elliott U.S. Pat. No. 4,381,571 which shows an articulated mattress spring that is adapted to fit on top of and rest on a separate simple rectangular bed frame. The Elliott mattress frame includes large stationary "L" shaped side sections with cross members to provide support for axially oriented motor and screw assemblies that drive complicated four bar linkages at the four corners of the module that serve to raise and lower the head and leg sections of the mattress support. While Elliott suggests that these parts, numbering literally hundreds, may be disassembled for shipment it is realistically not practical to have the purchaser reassemble this complex device in his or her home.
A similar articulated bed is illustrated in the Neumann U.S. Pat. No. 4,120,057 and it shows a power system for an articulated mattress support and, like the Elliott design, is adapted to fit into a bed frame. The problem with the Neumann device is that it requires a large rectangular frame the size of the bed frame itself so that no size reduction is practically possible in the Neumann system.
Furthermore in the Elliott device the power module with drive motors, gearing and rocker shafts, requires that the rocker shafts be mounted in outboard bearings, i.e. bearings in the large rectangular frame described above and such outboard bearings denigrate the capability of shipping the bed in easily carried containers without requiring any significant reassembly at the purchaser's location.
Other articulated beds are illustrated in the Muir U.S. Pat. No. 1,397,773 and the Szemplack, et al. U.S. Pat. No. 3,051,965. The patent to Muir also shows a device for adjusting the articulated bed. Double motor-type systems are shown in the Taylor U.S. Pat. No. 2,500,742. Another standard articulated bed frame is illustrated in Hanning, et al. U.S. Pat. No. 3,921,230.
In our U.S. Pat. No. 5,063,623, we disclose a power module for an articulated bed assembly that fits into a completely standard bed frame. A mattress support is provided that has wooden planar panels hinged to one another with a stationary central section adapted to be bolted to the top of the standard bed frame, a pivotal head section, and pivotally interconnected thigh and foot sections. The power module has an elongated housing that supports separate electric drive motors, one for the head section and one for the thigh and foot sections. Drive gearing in the module transmits power from the motors to transversely mounted rocker shafts that have rocker arms at the ends thereof that respectively pivot the head and leg sections upwardly and downwardly with a suitable wand-type control that reversely controls the two motors.
In this patent, the power module was connected to the underside of the central stationary section of the mattress support.
In our U.S. patent application Ser. No. 308,412, we disclose an articulated bed having a modified standard bed frame that supports an independent power module replaceable without disassembly from the frame. The modified frame is of the well known horizontally collapsible angle iron-type with castered legs. The framing includes a pair of side rails each having head and foot rail portions pivotally connected thereto at their ends for packing and shipping, that interengage one another when assembled in the home.
The modification of the frame in our parent patent was the provision of inverted side rails so that the horizontally flat parts of the angle irons are at the top, and its legs are somewhat lengthened to accommodate the underslung power module. After the frame is assembled in the home, a pair of "U" shaped cross members are attached across the frame and the power module is affixed to the tops of these cross members.
This design had many of the advantages of the power module and standard bed frame disclosed in our noted patent application.
The U.S. Ser. No. 308,412 design also included a mattress support is provided that has wooden planar panels hinged to one another with a stationary central section, a pivotal head section and pivotally interconnected thigh and foot sections. The power module has an elongated housing that supports separate electric drive motors, one for the head section and one for the thigh and foot sections, and drive gearing that transmits power from the motors to transversely mounted rocker shafts that have rocker arms at the ends thereof that respectively pivot the head and leg sections upwardly and downwardly with a suitable wand switch that reversely controls the two motors.
An important aspect of that invention was the housing for the drive module provides the sole pivotal support for these two rocker shafts. As noted above these rocker shafts have previously been journaled inside frame members that require the drive module and the side frame members to be shipped as a unit from the manufacturing location to assembly location or from assembly to ultimate purchaser, because frequently the receiving party cannot technically provide the proper assembly. With the 308,412 module final set up is reduced and the power module can be shipped in a much smaller container in its completely assembled form.
Another advantage in that power module was it could be removed as a unit from the frame cross member for repair or replacement.
The U.S. Ser. No. 308,412 unitary power module, i.e. the elongated housing containing the two drive motors, the two rocker shafts, the rocker arms and interconnecting gearing, offers the manufacturer a variety of marketing options without requiring disassembly of the power module. One option is the power module manufacturer can ship the power module fully assembled to the articulated bed manufacturer, frequently skilled in wood working and to a limited extent welding, but not skilled in power drive systems. Such bed manufacturers would construct the wood planar mattress support and simply attach the power module to the cross frame member. No other interconnections would be required to complete the power module and frame assembly in operative cooperation. The articulated bed manufacturer then sells this completed assembly as a unit.
The advantage of the 308,412 invention over that shown in our parent patent, was the present design was an entire bed assembly that could be packaged for shipment to the ultimate user in three compact packages, one including the power module, one including the collapsed modified bed frame and "U" shaped cross members, and the final one containing the collapsed mattress support.
It is a primary object of the present invention to ameliorate the problems noted in the above prior art and to provide improvements over our prior designs, at least in certain aspects.